Clamping mechanism for planer rails



Nov. 10, 1925 1,560,696

C. KNOWLES CLAIPING MECHANISM FOR PLANER RAILS Filed Aug. 13, 1920 .9 4 F a o 10 I o o H L 14 a n 3 Me/wtoz 8p Mew wgmw Patented Nov. 10, 1925.

UNITED STATES 1,560,696 PATENT o-FFl'cE;;',,

. CARROLL KNOWLES, or HARTFORD, oonnno'rrcu'anssrcnon To PRATT aiwHI'rN Y I COMPANY, on NEW YORK, N. Y., A CORPORATION on NEW JERSEY.

CLAMPING MECHANISM For; PLANER RAILS.

Applicationfiled August 13, 1920. Serial No. 403,380. 3

To all whom it may be concem:

Be it knownthat I, CARROLL KNOWLES, a citizen of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvementsin Clamping Mechanisms for Planer Rails, of which the following is a specification.

This invention relates to planers and par- I ticularlv to a mechanism for clampingthe cutter-supporting cross rail to the uprights thereof, and it is the general object of the invention to provide an improved mechanism for performing this function.

In machines of the type illustrated herein the cutter-supporting rail is vertically adjustable 0n the uprights and clamping devices are mounted on the rail in position to engage the uprights to clamp the rail thereto in its adjusted position. It has been heretofore proposed to provide two clamping members, one for each upright, and a single means having-a bearing action against the clamping members to perform the clamping operation. In such a construction the two clamping members must be exactly alike and must be adjusted to exactly correspond with each other. They must fit the rail'and the two uprights with an equal precision if the clamping action on the two uprights is to be the same. However, since such accuracy cannot be maintained, the major portion or all of the clamping action may take place on one upright. Such upright must r therefore withstand the thrust of the tool while the clamp at the other end of the rail may be loose and therefore perform little or no holding or clamping action. It is accordingly an object of the present invention to provide a clamp-operating means wherein the clamping effect on the two uprights is equal. This object may be accomplished in a variety of ways of which the one illustrated herein is an example.

' Referring to the figures of the drawing: Figure 1 is a front elevation of a planer comprising the present invention. 7

Fig. 2 is an enlarged horizontal transverse section through the planer on the line 22 of Fig. 1 and illustrating the improved cutter-supporting cross rail clamping means. Fig. 3 is a detail view of the right end of the cross rail and illustrates the clamp-operating handle.

Referring more specifically to the drawing by reference characters, 1 indicates the base, 2 the reciprocating table thereon, and 3 the uprights mounted on the base at opposite' sides of the tabl'e." 4 indicates the out ter-supporting rail fmounted onfth'e uprights 3 and ada'pted to be" vertically adjusted thereon by means of'screws 5 threadedly en gaging nuts or lugs 5 on therail. Aside 7 head cutter support 6 is mounted on one upright 3 and may be adjusted vertically'there on by means of a screw 7. Cutter hea ds 8 mounted on the rail 4 may {be adjusted horizontally therealong by means of screws 9 and 10; The cutter feeding mechanism which within itself forms no partof this nvention is shown generally at 13 and 14 and comprises the usual rack and pinion and ratchet mechanisms to the feedscrews 9 and 10 and screw 7. Th cutters are adapted to the adjusted toward and from the work by means of handwheels 6? and 8*. Belts 11 and 12 operating on belt pulleys 11 and 12 respectively are provided for reciprocating the table 2.. i The clamping mechanism comprisingthe present invention is shown more clearly in Fig. 2 wherein clamping means, as the two levers'15, is mounted-'on'the rail, one1lever bemg pivotedv adjacent each upright. Each clamping lever comprises a long arm 15*" and a short arm 15,-eachlever being secured at its fulcrum to the rail "by "means of: a

tap bolt 16passing looselythrough the'lever' and threade'dly engaging the rail. A pair of washers 17 having curved engaging sur action to engageythe surface 18 atthe rear of its respective upright.

In accordance with the invention I pro-1 vide a single means for engaging and operating the clamping leversand I mount a differential or equalizing member. between this means and the clamping levers-whereby an equal clamping pressure will be imparted from the levers to the uprights. The .operating means illustrated herein comprises a cam 19 preferably formed as an eccentric on a shaft 20 parallel with the rail 4 and adaptedto be operated by a handle 21. To avoid friction a roller 19 is preferably mounted On the cam 19. The equalizing 15 of each lever is adapted in the clamping 9 member comprises a plate 22 having pins 23 threaded therein and loosely engaging in bores 24 in the free ends of the long arms 15 As illustrated, the plateis adapted to be engaged directly by the roller 19*.

In Fig. 2' and in the full lines of Fig. 3 the rail is shown as clamped to the uprights. When it is desired to adjust the rail vertically the handle 21 is-moved to the position illustrated in dot-and-dash lines in Fig. 3, which movement releases the pressure of the roller 19 on the arms 15 and likewise releases the pressure ofthe arms 15 on the uprights 3, thus leaving the rail free to slide vertically on the uprights. To clamp the rail in its adjusted position the l1andl'e21 is moved to the full-line pesition illustrated in Fig. 3. This action of the shaft through the cam 19 thereofforees the-roller 19 against the plate 22 which, being loosely mounted in the ends of the arms 15, exerts equal pressure against such arms and likewise exerts an equal clamping pressure of the arms 15 against the uprights 3. 'As will be noted, the use of the equalizing plate 22 assures an equal clamping pressure at both ends of the rail even though the levers 15 are unequally adjusted on the rail and regardless of any foreign matter which may get between the clamping surfaces 18 of the uprights and the arms 15.

What I claim is:

1. In a machine tool, the combination cf two supports, a member mounted for sliding movement on such supports, a clamping means pivoted on the member adjacent each support, and cam operated means including a differential connection between and in operative connection with the two clamping means for operating the same with equal pressure against the two supports.

2. In a machine tool, the combination of two supports,, a tool-supporting member mounted for sliding movement on such supports, a clamping member mounted on the tool-supporting member adjacent each support, means for forcing the clampingv mem bers into clamping engagement with the two supports, and an equalizing member between the said means and the clamping members whereby the clamping members are operated with an equal pressure against the two supports. V

i In almachine tool, the combination of two uprights, a cutter supporting. rail mounted for vertical sliding movement on the uprights, a clamping lever mounted on the rail adjacent each. upright, a cam on the rail for forcing. the clamping levers into clamping engagement with the: uprights, and

an equalizing member between the cam and clamping levers whereby the levers are operated with an equal pressure against the two uprights. V V V 4:. In a machine tool, the combination of two uprights, a cutter-supporting rail mounted for vertical sliding movement on the uprights, a clamping lever pivoted to the rail adjacent each upright, each lever comprising a long and a short arm, the short arm of each lever being adapted to clamp ingly engage its upright, a cam on the rail for operating the levers to clamp the rail to the uprights, and an equalizing member loosely connected to the long arms of the levers and adapted to be operated on by the cam whereby in the clamping operation the pressure exerted by the cam is divided equally between the two levers.

5. In a machine tool, the combination of two uprights, a cutter-supporting rail mounted for vertical sliding movement on the uprights, a clamping member mounted on the rail adjacent each upright, a rotary cam on the rail for operating the' clamping members, and an equalizing member between the cam and the said clamping members whereby the clamping action of the cam isv distributed equally to the clamping members against their respective uprights.

6. A rail clamping device for machines of the character described, comprising a rail, a pair of supports therefor, a pair of clamps pivotally secured to said rail, andhaving clamping surfaces for engaging said supports and means for operating saidclamps comprising an equalizer element, operatively connected to the same.

7. A-rail clamping device for machines of the character described, comprising a rail, a pair of supports therefor, a pair of clamps pivotally secured to said rail, and having clamping surfaces for engaging said supports and means for operating the same comprising a member free to move automatically to compensate for unequal pressure exerted against the clamps.

8. A rail clamping device for machines of the character described, comprising a rail, a palr of supports therefor, a pair of clamps pivotally fastened to the said rail and having clamping, surfaces adapted to engage the said supports, a rotary shaft extending lon gitudinally of the said rail, and means operable by the rotation of the said shaft and adapted to actuate the said clamps.

In testimony whereof, I hereto ,afiix my signature.

oannort KNOWLES. 

